arXiv subjects

A. Szenes

Publications and source records attributed to A. Szenes.

4 recordsLinked to original sources

arXiv2023

Radiation pattern and source size of particles in nanoplasmonic fusion

For the angular radiation patterns of proton, deuteron or alpha emission we present a way using particle-in-cell simulation of laser induced nanoplasmonic fusion. The differential Hanbury-Brown and Twiss analysis is widely used in astrophysics and in relativistic heavy ion physics to determine the source size of emitted particles. Here, we show how this method could be adopted for inertial confinement fusion. This method aims to determine the parameters of emitted nuclei after the fusion target ignition. In addition to spatial volume, the method can detect specific space-time correlation patterns connected to the collective flow post-ignition. In the NAPLIFE project our aim is to avoid thermalization and fluidization as much as possible at each stage of the fusion process. As the original laser beam is non-thermal and not equilibrated in any way it is obvious that we can minimize energy loss if we exploit the initial available energy in a non-thermal way. The detailed dynamics of deuterium and alpha production is not aimed at and not addressed by this paper.

physics.plasm-ph↗

arXiv2021

Comparative study on the uniform energy deposition achievable via optimized plasmonic nanoresonator distributions

Plasmonic nanoresonators of core-shell composition and nanorod shape were optimized to tune their absorption cross-section maximum to the central wavelength of a short pulse. Their distribution along a pulse-length scaled target was optimized to maximize the absorptance with the criterion of minimal absorption difference in between neighbouring layers. Successive approximation of layer distributions made it possible to ensure almost uniform deposited energy distribution up until the maximal overlap of two counter-propagating pulses. Based on the larger absorptance and smaller uncertainty in absorptance and energy distribution core-shell nanoresonators override the nanorods. However, optimization of both nanoresonator distributions has potential applications, where efficient and uniform energy deposition is crucial, including phase transitions and even fusion.

physics.optics↗

arXiv2021

Active individual nanoresonators optimized for lasing and spasing operation

Plasmonic nanoresonators consisting of a gold nanorod and a spherical silica-core and gold-shell, both coated by a gain layer, were optimized to maximize the near-field enhancement (NF-type) and far-field outcoupling (FF-type), and to enter into the spasing operation region (NF-c*-type). It was shown that in case of moderate concentration the nanorod has more advantages: smaller lasing threshold, larger slope efficiency and achieved intensities in the near-field, in addition in FF-type system smaller gain and outflow threshold, earlier flipping and larger far-field out-coupling efficiency. However, the near-field (far-field) bandwidth is smaller in for NF-type (FF-type) core-shell nanoresonators. In case of larger concentration although the slope efficiency and near-field intensity remain larger and the far-field redistribution is more efficient in case of the nanorod, the core-shell nanoresonator is more advantageous, taking into account the smaller lasing, outflow, absorption and extinction cross-section thresholds, as well as the larger internal and external quantum efficiencies. In addition to this the bandwidth of core-shell nanoresonator is also smaller. It was also shown that the strong-coupling of time-competing plasmonic modes accompanies the transition from lasing to spasing.

physics.optics↗

arXiv2016

Plasmonic structure integrated single-photon detectors optimized to maximize polarization contrast

Numerical optimization was performed via COMSOL Multiphysics to maximize the polarization contrast of superconducting nanowire single photon detectors (SNSPDs). SNSPDs were integrated with four different types of one-dimensional periodic plasmonic structures capable of mediating p-polarized photon selectivity to the niobium-nitride superconducting nanowire pattern. Optimization with two different criteria regarding the maximal tilting resulted in wavelength-scaled periodic integrated structures, which have different geometrical parameters, and exhibit different polar angle dependent optical response and dispersion characteristics, as well as accompanying near-field phenomena at the extrema. Polarization contrast of 6.37*10^2 and 3.28*10^2 - 6.86*10^11 and 1.42*10^11 - 1.81*10^13 and 7.87*10^12 - 1.90*10^3 and 1.15*10^5 can be achieved in nanocavity-, nanocavity-deflector-, nanocavity-double-deflector-, nanocavity-trench-array-integrated P-SNSPDs optimized with 85 degree and 80 degree criterion regarding the maximal tilting.

physics.optics↗